Jan Smith Donaldson and Sam Donaldson arriving at the Gridiron Dinner in March 2011. (Richard A. Lipski for The Washington Post)

Another power couple on the rocks: Sam Donaldson and Jan Smith Donaldson.

The veteran ABC newsman, 78, and his journalist wife of 29 years quietly separated several months ago, her attorney confirmed to us Wednesday.

“They remain on good terms with each other and are hopeful they’ll be able to resolve their economic issues,” lawyer Sandy Ain said.

No reason given for the split, and the couple has not yet filed for divorce, said Ain: “It’s unclear where this is ultimately headed.”

The separation is the latest headline for the high-profile couple, who split their time between Washington and their ranch in New Mexico. Just last month, Sam was arrested in Delaware for a DUI; a court date is pending.

The Donaldsons with ABC bureau chief Robin Sproul, right, at a 2005 reception honoring his 42 years at the network. (Rich Lipski/The Washington Post)

The couple married in 1983 (his third) at the height of his fame as an outspoken, colorful White House correspondent. They had met a few years before, when she worked at ABC as an administrative assistant; he proclaimed to colleagues at the time of their engagement that this relationship “is forever, until I expire.” She told the Post shortly after their wedding that her older colleague “really swept me off my feet in terms of energy and excitement.”

He has held several jobs at the network and continues as an analyst. Jan, 57, worked for years as a television reporter for the local Fox affiliate and has spent the past decade serving on nonprofit and charitable boards. The two have used their combined visibility and contacts to become advocates for cancer research after he received a diagnosis of melanoma almost 20 years ago; they’re also popular figures in Washington’s social and philanthropic scenes.

But their ranch — in Sam’s family for decades — has been the source of several headaches for the couple: an ongoing controversy for receiving federal crop subsidies; a brutal murder of the ranch foreman and two members of his family in 2004; and, last year, when several thousand acres were destroyed by the devastating wildfires in the state.

The couple has no children together; Sam has four from his previous marriages. His lawyer declined to comment on the separation.

Earlier: Sam Donaldson arrested for DUI, 12/19/12

Wildfires consume 21,000 acres on Sam Donaldson ’s New Mexico ranch, 7/5/11

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